Energy efficiency for all energy loads!
The concept for building a passive house swimming pool focuses on the high-quality building envelope with reduced risk of condensation (insulated, airtight, good window quality, thermal bridge free construction) and ventilation system (heat recovery, recirculation, dehumidification). And also it aims to achieve an energy-efficient solution with all other energy loads inside the building that need to be considered, such as:
-Electricity demand for swimming pool technology
-Heating energy demand for hot water (mainly showers)
-Demand controlled ventilation with heat recovery
-Fresh water and heating energy demand of the pool water
-Electrical efficiency of other energy applications, e.g. lighting, ventilation, building systems etc.
-High efficiency of any other leisure areas or additional facilities, e.g. water features, sauna, spa, fitness equipment, catering etc.
Did you know that…?
1/ The first two passive house swimming pools were completed in 2011 in Germany (Bambados in Bamberg and the Lippe-Bad in Lünen).
2/ Compared to typical buildings that are heated to 20 °C, the transmission heat losses of the exterior building components of indoor swimming pools with a warmer indoor temperature of ca. 30-32 °C are considerably higher, as are the savings with each additional centimetre of thermal insulation (meaning that additional insulation is very cost-effective).
3/ Due to the high indoor temperature and evaporation of the swimming pool water, there is typically a year-round heating demand with average indoor humidity of 52%.
4/ The total energy demand can be reduced by increasing the humidity level in the swimming pool. Note that for structural protection reasons, relative humidity of 64 % should not be exceeded for longer periods.
5/ Windows and curtain wall façades have higher losses than the insulated wall and therefore lower surface temperatures. Due to the high thermal quality of windows (triple glazing low-e glazing, thermally separated frame profiles), there is a lower risk of condensation and no need to blow warm dry air onto them to prevent condensation. Therefore there are more options where to put the supply air devices in building for air recirculation.
6/ Better U-values are strongly recommended from the economic viewpoint in the case of higher indoor temperatures (below 0.10 W/(m²K)).
7/ No penetration through the building envelope is highly advised (no drainage system on the inside, thermal separation of balconies, thermal bridge free construction, minimalisation of ventilation ducts through the roof, etc.).
8/ An airtightness level of q50 ≤ 0.4 m³/(hm²) is recommended for indoor swimming pools. The constantly evaporating water must be removed continuously
9/ The ventilation system for the pool hall has two main tasks: ensuring a good quality of air (hygienic ventilation for the removal of disinfection by-products in particular) and dehumidification of the pool hall air. Ventilation units with highly efficient heat recovery are appropriate for keeping low the energy losses due to ventilation.
10/ AHU device is balanced (outdoor and exhaust air) or there is slight negative pressure inside the building. Commission and data monitoring (BMS with a variety of sensors to also operate the swimming pool technology) is necessary for optimisation and running of the swimming pool.
Download the guidelines for the Passive house concept for the indoor swimming pools by Passive House Institute (link here).